ASME VIII Vessel flange angular tolerance

[andrewgbc]

I'm looking at a vessel designed to ASME Sect VIII Div 1. We are concerned that 2 of the nozzles may be misaligned.
Does sect VIII Div 1 or another code specify the max allowable angular tolerance for vessel nozzles?
Customer and vendor drawings do not show any tolerances, and I don't have access to customer specifications at this time.
Thanks in advance
Andrew

 

[vesselfab]

ANGULAR?

out of angular orientation?

pipe out of square with vessel?

flange out of square with pipe?

flange out of 2-hole?

vessel has lots of angles

 

[andrewgbc]

Apologies, even cylindrical vessels have many angles.

The vessel plan view shows the nozzle orientation with respect to 0degrees (e.g. Nozzle A at 90 degrees, Nozzle B at 125 degrees).
I want to know if there is an allowable tolerance for this angular orientation in a plan view of a vessel. So for example Can Nozzle A be at 90 degrees +/- 2 degrees? +/- 10 degrees?

 

[doct9960]

andrewgbc,

Does sect VIII Div 1 or another code specify the max allowable angular tolerance for vessel nozzles?

No.

Most of the customer specs I've seen usually specify alignment of nozzle flange face to be within 0.25° of specified plane.

 

[vesselfab]

the code does not

normally 1/2* out of orientation is allowed

if it is allready built, fill out NCR and request user to take as is. Pipe may not be made and changes can be accomodated. even if they have to modify pipe, it's cheaper than cutting out a nozzle

 

[andrewgbc]

Thanks for your help. As I say I don't have the customer's specs but we're looking at about 2.5 degrees out compared with the drawing.
We are planning to do a direct replacement of an existing vessel, and reconnect the existing pipe, so the nozzle orientation is pretty critical, to minimise additional work.
Thanks once again.

 

[MrBTU]

We use TEMA F-1 and F-2

 

[pennpiper]

"We are planning to do a direct replacement of an existing vessel, and reconnect the existing pipe, so the nozzle orientation is pretty critical, to minimize additional work."

"Beware" This is where the Client, the Project Manager and the Field Construction Manager (of this new work) will point the finger of blame at the piper who did the original piping layout years before.

He or she should have made allowances for the possibility that any vessel built then or today is allowed a wider range of nozzle location tolerance error with-out being considered a miss-fabrication. On the other hand the piping is not allow to be off, it must be in compliance with the PFI Standards.